To treat an ischemic heart disease, an intravascular treatment that is a minimally invasive treatment is often employed in recent years. The intravascular treatment is conducted fluoroscopically using an X-ray imaging apparatus. The intravascular treatment may need two to three hrs to give, and the dose of the patient and medical staff poses a problem. Hence, to reduce the dose, the object is protected using a protective plate, or the imaging rate is decreased. However, the X-ray dose reduction effect of these measures is not sufficient.
On the other hand, a technique called ROI fluoroscopy is known (for example, Jpn. Pat. Appln. KOKAI Publication No. 2003-265449). ROI fluoroscopy is a technique of performing X-ray imaging only for a region of interest designated by the operator. Adopting the ROI fluoroscopy allows to actually properly reduce the exposure dose of the object as compared to a case in which normal X-ray imaging is executed.
However, the operator of the X-ray imaging apparatus cannot know specifically how much the exposure dose is decreased as compared to normal X-ray imaging.
It is an object to provide an X-ray imaging apparatus that allows the operator to recognize the degree of exposure dose reduction implemented by executing ROI fluoroscopy as compared to a case in which normal X-ray imaging apparatus is (to be) executed, and a program.